This is the same John who wrote the Gospel. Upon first reading of 1 John, the similarities between the letter and the Gospel are obvious.
At the end of the first century, John became a prominent leader in the church at Ephesus and the outlying region. Refer again to the Gospel readings for further notes on the character and context of John. In the tone of a wise and loving pastor/mentor, John writes this letter to the church to encourage them to not be persuaded by the pressures of the world and the teaching of false teachers to stray from the pure gospel of Jesus and be sucked into destructive patterns. The message of 1 John could be summarized in the following sentence, “Walk in the light of God’s truth, which is love, stay away from the darkness of the world, and overflow with love for each other.”